Accident lnvestigation Coordinating Committee
Alrcraft Accldent Report 2O1llO1
Final Report on the Accident to Viking Air DHC-6-300, 8Q-TMV Velana International Airport, Maldives 27 May 20L7 Accident Investigation Accident Report: 20L7 llt Coordinating Committee 8Q-TMV accident at Velana International Airoort
lntroduction Maldives is a signatory to Convention on International Civil Aviation (Chicago t944) which established the principles and arrangements for the safe and orderly development of international air transport. Afticle 26 of the Convention obligates Signatories to investigate accidents to civil aircraft occurring in their State.
This investigation has been conducted in accordance with Annex 13 to the Chicago Convention, the Civil Aviation Act 212012 and the Civil Aviation Regulations. The sole objective of this investigation and the Final Repoft is to prevent accidents and incidents. It is not the purpose of this investigation to apportion blame or liability.
The AICC was assisted by the Maldives Civil Aviation Authority (CAA), Trans Maldivian Ainnrays, the Maldives National Defence Force and the Maldives Police Seruice.
The recommendations in this repoft are addressed to the C.AA, unless otherwise stated.
All times in this report are in local time unless stated otherwise. nme difference between local and UTC is +5 hrs.
Mr. Abdul Razzak Idris Chairperson ra+orrns Accldent Investigation Coordinatlng Committee
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Table of Contents
Introduction ...... 2 Synopsis ...... 5 1 Factual information ...... 6 1.1 History of the flight ...... 6 1.2 Injuries to persons ...... 8 1.3 Damage to aircraft ...... 8 1.4 Other damage...... 9 1.5 Personnel information ...... 9 1.6 Aircraft information ...... 10 1.7 Meteorological information ...... 13 1.8 Aids to navigation...... 13 1.9 Communications ...... 13 1.10 Aerodrome and approved facilities ...... 13 1.11 Flight Recorders...... 13 1.12 Wreckage and impact information ...... 14 1.13 Medical and pathological information ...... 15 1.14 Fire ...... 15 1.15 Survival aspects ...... 15 1.16 Tests and research ...... 16 1.17 Organisational and management information...... 16 1.18 Additional information ...... 18 1.19 Useful or effective investigation techniques ...... 19 2. Analysis ...... 20 2.1 General ...... 20 2.2 Aerodynamics ...... 22 2.3 Flight crew ...... 22 2.4 Weather ...... 22 2.5 Crew training ...... 22 2.6 Survival Aspects ...... 22 3. Conclusions ...... 23
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3.1 Findings ...... 23 3.2. Causes ...... 23 4. Safety Recommendations ...... 24 4.1 Recommendations to the MCAA ...... 24 4.2 Recommendations to the Operator ...... 24 4.3 Recommendations to the Type Certificate and Supplementary Type Certificate holders ...... 25 5. Appendices ...... 26 5.1 Flight Release ...... 26 5.2 Damages to the aircraft ...... 28 5.3 List of Abbreviations ...... 37
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Aircraft Accident Report No: 2017/01
Owner Beau Del Leasing Inc Registered Owner Trans Maldivian Airways Pvt. Ltd. Operator Trans Maldivian Airways Pvt. Ltd. Aircraft Type Viking Air (De Havilland) DHC-6-300 Nationality Maldivian Registration 8Q-TMV Manufacturer’s Serial Number 625 Place of Accident North Right Water Aerodrome in Velana International Airport Latitude: 041153N Longitude: 0733210E Date and Time 27 May 2017 at 0835 hrs
Synopsis On 27th May 2017, DHC-6 aircraft, registration number 8Q-TMV owned by BEAU DEL LEASING
INC and operated by Trans Maldivian Airways was on a chartered flight from Rangali Island resort, Conrad Maldives to Velana International Airport. The flight was conducted in accordance with the visual flight rules (VFR). There were nine passengers, two pilots and one cabin crew on board the aircraft. The accident occurred during landing on the water aerodrome at Velana
International Airport.
The aircraft, while landing on the North Right Water Runway, touched down on the left float and bounced. After the second bounce, while the aircraft was still airborne, it banked to the right dipping the right wing tip in the water. The aircraft then abruptly veered to the right and crashed.
The passengers and crew were able to evacuate before the aircraft submerged completely. No passenger or crew sustained any injuries and they were rescued and safely taken to Hulhumale’
Hospital.
The accident site was secured by MNDF Coast Guard personnel and accident investigation was initiated immediately. The aircraft wreckage was salvaged and brought to a secured place for further investigation on the same day.
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1 Factual information
1.1.1 Background
On the previous day (in the evening) the aircraft underwent non-routine maintenance
and was released for flight. There were no deferred defects. Prior to the accident, the
aircraft had flown a thirty eight minutes (block time) uneventful sector.
On the day of the accident both the pilots reported for duty at 0700 hours at TMA base.
It was the first time that both the pilots flew together. No appropriate introductions of
the crew were made before the flight (crew briefings).
The company usually schedules a sequence of flight sectors back to back and issues a
combined “flight release” for these flight sectors. On the day of the accident five such
sequences of flights were scheduled for the crew on the same aircraft. The airline “flight
release” document contains three parts. These are the operational flight plan, passenger
manifest and the baggage manifest.
The crew began the day by preparing the aircraft for flight. Water was pumped out of the
floats and the number of strokes required to empty the floats were recorded in the “float
status report form”. Company procedures require to check the float serviceability status
at the start and end of each day. The co-pilot pumped the right float while the cabin crew
pumped the left float. According to the crew, the number of pump strokes to empty the
water from the floats were within the limits specified in the company procedures. The
crew carried out the pre-flight and walk-around checks prior to the first flight of the day.
No abnormalities were recorded or reported by the crew.
The roundtrip flight, Male’-Rangali-Male’ was released with 3 crew members (2 flight crew
and 1 cabin crew) and 11 passengers from Male’ to Rangali. As per the flight release
document, the aircraft was loaded with 304 lbs of baggage and 990 lbs of fuel, with a take-
off mass of 11,741 lbs.
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The PIC was PF for the first sector of the flight. Taxi-out, take-off, cruise and the landing
at Rangali were normal, according to the crew. The aircraft landed at Rangali at 0754
hours.
The aircraft took off from Rangali for the second sector of the flight with same crew
members (2 flight crew and 1 cabin crew) and 9 passengers. As per the flight release
(manifest), the aircraft was loaded with 111 lbs of baggage and 670 lbs of fuel, with a take-
off mass of 11,117 lbs. The flight duration of this sector was approximately 30 minutes.
The PIC taxied the aircraft through the coral area of Rangali lagoon. When cleared of the
coral area, the PIC handed over control of the aircraft to the co-pilot.
According to the flight crew, no abnormalities were observed throughout the flight. From
the take-off at Rangali to approach for landing at Velana International Airport, and until
the first touch down the flight was uneventful. The approach to land was normal.
While landing left float
touched the water first,
then the aircraft bounced
and ballooned; then landed
on the left float for a second
time, and bounced again.
Then the aircraft was
banking excessively to the
right digging the right wing
tip in the water, making the Figure 1: Aircraft position when the investigation team arrived to the site aircraft veer to the right.
Then the aircraft crashed on water banking to the left with left float digging into water.
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Injuries Crew Passengers Others Fatal - - - Serious - - - Minor/None 3 11 -
The aircraft was substantially damaged.
The investigation identified the following damages to the aircraft;
Damage to outer skin of rear baggage compartment door. Large dents on the
entire surface.
Large dent and puncture on step strut attachment point on fuselage aft of rear
baggage compartment door.
Step strut attachment point broken off leaving a hole. Cracks propagating from
the damaged area.
7” Puncture of fuselage skin above port side cabin window 6.
Step strut attachment point sheared off leaving hole of approximately 3” diameter
on the fuselage skin below port side Pilot door.
Sliding window on the port side deformed and pulled out of groove.
Multiple cracks, fractures and major dents on the door. Door latch broken.
Fuselage skin under door damaged and ripped off.
Nose cone crushed inward due to impact when aircraft was being lowered to M5
dock.
Water damage to all flight deck avionic equipment and furnishings.
Fuselage skin crumpled and deformed on top and side of fuselage where ropes
went around it to hoist the fuselage out of water. Rivets sheared and mating
flanges exposed.
Frame 239 cracked.
Fuselage top skin and stringers bent and crumpled above ‘A Frame’.
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Rudder was found to be cracked and split in half.
Damage to R/H wing from STA 376.20 to 272.00 including damage to aileron.
Damage from STA 376.20 to 322.00 L/H Wing.
Cracks on outboard longeron of R/H and L/H engine.
Impact damage of L/H and R/H propellers. Both engines were submerged in water.
Deformation of floats and spreader bars of both L/H and R/H floats. R/H float
sheared off on impact. L/H float obtained substantial damage on impact.
Refer Annex A of the report to view the damages to the aircraft.
None
1.5.1 Commander Age: 60 Licence: Airline Transport Pilot Licence (Aeroplanes) Aircraft Ratings: DHC-6 (on Maldivian licence) Last proficiency check: 28 February 2017 Last instrument rating 28 February 2017 renewal: Last line check: 16 March 2017 Last medical: Class 1 (08 March 2017) Flying experience: Total all types: 15,991 hours On Type: 12,834 hours Last 90 days: 180 hours 53 minutes Last 28 days: 41 hours 46 minutes Last 24 hours: 5 hours 8 minutes Previous rest period: 13 hours
1.5.1 Co-pilot Age: 28 Licence: Commercial Pilot License (Aeroplanes) Aircraft Ratings: DHC-6 Last proficiency check: 25 January 2017
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Last instrument rating No IR renewal: Last line check: 14 April 2017 Last medical: Class 1 (30 October 2016) Flying experience: Total all types: 537.6 hours On Type: 342.1 hours Last 90 days: 229 hours 29 minutes Last 28 days: 82 hours 39 minutes Last 24 hours: 7 hours Previous rest period: 11 hours 35 minutes
1.5.1 Cabin crew Age: 23 Licence: Cabin Crew Licence Last recurrent training: Line check Last medical: Class 3 (19 November 2015) Previous rest period: 12 hours 15 minutes
1.6.1 General information
The DHC-6-300 “Twin Otter” is an unpressurised, all-metal, high wing aircraft powered by
two Pratt & Whitney PT6A-27 engines driving Hartzell three-blade, reversible-pitch, full
feathering propellers. The aircraft is designed for seating two pilots, side by side with dual
controls and standard flight instrumentation.
Manufacturer: Viking Air (De Havilland) Registration: 8Q-TMV Powerplants: 2 x Pratt & Whitney PT6A-27 turboprop engines Manufacturer’s serial number: 625 Year of construction: 1979 Airframe hours at time of 57,523.79 hrs accident: Certificate of Airworthiness: Normal category, issued on 24 December 2009 Airworthiness Review Certificate: Issued on 11 April 2017
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1.6.2 Cabin layout and configuration
The aircraft was in float configuration with Wipaire 13000 floats installed. The aircraft
cabin was configured for 15 passengers plus one cabin attendant with baggage placed
near the right rear passenger door. The aft baggage compartment is used for loading
smaller luggage. The aircraft had four exits in the cabin and two exits in the cockpit. The
right passenger door is not used as an emergency exit; usually blocked with baggage.
1.6.3 Recent maintenance
The last scheduled maintenance Check was Equalised Maintenance for Maximum
Availability (EMMA) number 29 carried out on 06 May 2017 (at 57,449.93 TAT and 96,376
TAC). A scheduled Reverse Current Relay (RCR) replacement was carried out on 21 May
2017 and a scheduled Push-To-Talk (PTT) switch(R/H) replacement was carried out on 17
May 2017. On the 26 May 2017 (in the evening) the aircraft underwent non-routine
maintenance which was to replace a fuel flow indicator to clear a deferred defect and was
released for flight.
There were 11 unscheduled defects reported in the 30 days prior to the accident. The
details are as follows;
1. R/H Radio auto transmitting & heavy static (PIREP - cleared on 28/04/2017)
2. Very stiff aileron to the left on landing (PIREP - cleared on 01/05/2017)
3. L/H heavy aileron on the control (PIREP - cleared on 02/05/2017)
4. Aileron movement to the left side still very heavy & stiff. Slight right turning
tendency felt on approaches (PIREP - cleared on 03/05/2017)
5. Airstair door aft bottom cable broken strands (MAREP - cleared on 11/05/2017)
6. Stall bar on R/H wing is missing (PIREP - cleared on 13/05/2017)
7. L/H engine T5 going above limitations (PIREP - cleared on 17/05/2017)
8. L/H engine T5 indicator found cracked at connection point (MAREP - cleared on
17/05/2017)
9. Wind shield wiper starboard side (R/H) side INOP (PIREP - cleared on 18/05/2017)
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10. Controls are on a right bank in straight and level flight (PIREP - cleared on
24/05/2017)
11. R/H fuel flow INOP (PIREP – deferred on 25/05/2017 and cleared on 26/05/2017)
The last engine wash was done on 26 May 2017, while the last aircraft maintenance
release carried out on the same day.
The aircraft had no outstanding deferred defects at the time of accident nor were any
reported defects.
1.6.4 Flight controls
The flight controls consist of conventional, manually actuated primary flight controls
operated through cables, pulleys, and mechanical linkages. Rudder and elevator trim are
manually controlled and mechanically actuated; aileron trim is electrically actuated.
Secondary flight controls consist of hydraulically actuated wing flaps.
The flight controls were inspected after the aircraft was recovered from the seabed and
no issues were identified in the flight control system.
1.6.5 Powerplants
The aircraft was powered by two Pratt & Whitney Canada PT6A-27 turboprop engines.
Each engine is fitted with a Hartzell (HC-B3TN-3DY), three-bladed, constant speed, full
feathering and reversible propeller.
The pilots did not report any anomalies related to the engines or propellers.
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Meteorological information Male’ (VRMM) issued on 27th May 2017 at 0800 LT and 0900 LT.
Type and Area Date & Time in UTC Weather Remarks
METAR VRMM 270300Z 25011KT 9999 FEW018 Nil FEW019CB BKN270 30/60 Q1010 CB S NOSIG
METAR VRMM 270400Z 25012KT 9999 FEW018 Nil BKN270 30/26 Q1010 NOSIG
The aircraft was operating under Visual Flight Rules. Aids to navigation was not a factor
in this accident.
The aircraft was equipped with two VHF sets both of which were serviceable at the time of departure. The pilots were communicating with the ATC during approaching and landing.
Velana International Airport has three water runways. They are water runway North
Right/South Left, runway North Left/South Right and runway East/West.
The aircraft landed on the North Right water runway of Velana International Airport.
The aircraft was not equipped with a flight data recorder (FDR) or cockpit voice recorder
(CVR), nor were these required to be fitted under current Civil Aviation Regulations. It
should be noted that the AICC in its recommendations made after an accident that
occurred on 17 May 2004, recommended the CAA to re-examine the criteria of carriage
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for flight recorders on transport category aircraft certified to carry more than 9 passengers with a view to requiring all aircraft to carry at least a CVR.
Further, the AICC in its recommendations after the accident that occurred on 2 June 2009
recommended CAA to mandate installation of CVRs on all aircraft used for commercial
air transportation.
AICC in its recommendations after the accident that occurred on 2 July 2015
recommended CAA to review and consider implementing the previous recommendations
made with regard to mandating installation of CVR’s.
1.12.1 Accident site
The wreckage was at a depth of approximately 10-11metres on the seabed at North Right
water runway, Velana International Airport.
1.12.2 Examination of baggage
Examination of baggage revealed that one piece of baggage of a passenger was missing.
Further search for the missing piece was carried out by MNDF, however the baggage was
not recovered.
1.12.3 Salvage operations
The salvage operation of the wreckage was jointly carried out by MNDF and TMA
personnel, overseen by the investigators. The main challenge in the salvage operation
experienced by the team was the murkiness of the water caused by the ongoing dredging
works. This could have contributed to non-recovery of one of the steps which was
detached from the aircraft.
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The crew did not have any pre-existing medical conditions that may have contributed to
the accident. Medical examinations were performed on all crew members and there was
no evidence of alcohol, drugs or any toxic substance that may have contributed to the
accident.
No fire involved.
1.15.1 Emergency Locator Transmitter (ELT)
8Q-TMV was equipped with an Artex model C406-1 ELT (capable of transmitting on
121.5/243 and 406 MHz) fixed in the aft baggage compartment. The ELT was connected
by cable to an external roof-mounted antenna and to a remote cockpit switch.
No distress signals were received from the accident aircraft. The ELT was found attached
to the aircraft within the wreckage. The ELT was last serviced on 8 March 2017 and the
battery expiry is 1 April 2019.
1.15.2 Life jackets
The aircraft had crewmember life vest at every crew seat location and passenger life vest
under every passenger seat.
It was reported that only one of the passengers was wearing the life jacket who happened
to be someone that did not know how to swim. This passenger was apparently assisted
by the cabin crew in wearing the life jacket.
Unlike a previous accident involving a similar seaplane, in this particular accident, there
was no passenger who complained that they had any difficulties in removing the life vest
from the plastic protective covering.
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1.15.3 Evacuation
Immediately after the impact, Cabin crew, PIC and the FO collectively initiated evacuation.
Right emergency door of the aircraft was used for the evacuation.
No tests or researches were carried out as there were no technical defects identified
during the course of the accident investigation.
1.17.1 Company structure
Trans Maldivian Airways is a commercial air transport operator (with operator certificate
number MV.AOC.005) formed in October 1993. It operated as Maldivian Air Taxi until
February 2013 when the name was changed to Trans Maldivian Airways following the
merger of Maldivian Air Taxi and T.M.A. Ltd. The company currently operates a fleet of 46
DHC-6 aircraft providing charter services to resort islands.
The company also hold a maintenance management organisation approval (MV.MG.003),
a maintenance organisation approval (MV.145.025) and Approved Training Organisation
(ATO number: 005) issued by the MCAA.
1.17.2 Operations Manual
The Operations Manual (OM) was compiled with the express intention of complying with
Maldivian Civil Aviation Regulations and the Air Operator Certificate (AOC). The OM was
divided into several sections as follows:
Part A General
Part B Aircraft Operating Matters
Part C Route and Aerodrome
Part D Training
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1.17.5 Crew training
Operations Manual Part D covers DHC-6 type conversion and recurrent training courses.
First Officer
As per the training records from the operator, FO started flying on 10th January 2017 and
completed on 24th January 2017 with a total of 12.06 hours/10 Training flights. As per the
instructors (TRI) review he completed the training with standard performance and
repeated 1 training lesson to practice take-off, approach and landing. His progress was
noted as ‘acceptable’. He completed LPC on 25th January 2017 covering all the required
checks. As per TRE’s review he was safe and effective, average for initial type rating.
Supervised line flying of the FO commenced on 30th January 2017 to 14th April 2017 and
did a total of 183.67 hours and 351 sectors. According to the Operations Manual part D,
a minimum of 100 hours and 100 sectors and more than 3 recommendations from Line
Training PICs are required before a line check. LTCs’ commented ‘slow progress’ at the
beginning, however ‘progress good’ was noted in the later part of the Line Training. All
three recommendations from Training PICs for a line check was received by 10th April
2017. He completed the line check on 14th April 2017 and the review given by the
Examiner stated as “good solid performance”. As per the instructors’, Examiners’ and Line
Training PICs’ comments given on the training forms indicated him to be an average initial
type rating candidate.
PIC
As per the training records the PIC’s last line check was done on 28th February 2017 which
expires on 31st March 2018. In line check, he completed 1.25 hrs. As per the Examiner’s
comment given on the training forms, “no major errors”. The block time of Line Training
was 16.6 hrs/ 39 sectors.
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National Transportation Safety Board Accident Report AAR-91/01
The following is an excerpt of an investigation report (AAR-91/01) from the National
Transportation Safety Board (NTSB) following a similar DHC-6-300 accident which
occurred in 1989:
“Grand Canyon Airlines’ Pilot Operating Manual (POM) for the DHC-6…contains a caution
statement that; in a go-around with flaps extended, the nose will point below the actual
flight path. Pilots reported that applying power at low airspeeds when the flaps were fully
deployed would result in the airplane pitching up. The pilots further reported that positive
pressure against the control yoke was needed to stop or prevent this pitching tendency.
While some pilots reported that occasionally it was necessary to use both hands on the
control yoke to prevent the airplane from pitching up, no one reported that the control
forces exceeded the Federal Aviation Administration (FAA) maximum limitation of 50
pounds.
The NTSB investigation sought to determine the factors that might have caused the pilots
to lose control of the airplane during the go-around. During the dynamic situation while
the airplane was right wing down and heading for the side of the runway, the pilot’s
reaction might have been to raise the nose and add power for an anticipated go-around.
At airspeeds near stall, the downwash on the horizontal stabilizer tends to raise the nose
of the airplane, requiring the control yoke to be pushed forward to maintain a normal
pitch attitude for the same trim setting. If the pilot pulled back on the control yoke while
adding power, this could have resulted in the airplane lifting off in a nose high, power-on
stall or near-stall condition. In addition, the visual reference may have been misleading.
According to the operations manual for the DHC-6, with 40° (full flap is frequently referred
to as 40°, but is actually 37.5°) of flaps, the airplane’s deck angle is below the flight path
angle during a go-around. Therefore, an increase in pitch to a typical nose-up reference
attitude while the flaps were at 40° would increase the possibility of aerodynamic stall
and subsequent loss of lift.1”
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This is also supported by ‘Aviation Investigation Report A11W0144’ of Transport Safety
Board of Canada.
Desktop research was carried out on similar accidents occurred across the globe
involving DHC 6 aircraft to understand the causes that lead to the accident on 8Q-TMV.
1 National Transportation Safety Board, Grand Canyon Airlines flight Canyon 5, De Havilland Twin Otter, DHC-6-300, N75GC, Grand Canyon National Park Airport, Tusayan, Arizona, September 27, 1989, (Washington, D.C.: National Transportation Safety Board, 1991), page 13.
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2. Analysis
This analysis is focused on the crew coordination and handling of aircraft during the
landing and attempted go-around.
The flight from CON-MLE was normal until the first touchdown at MLE. No abnormalities
during the flight were reported. Examinations and tests carried out on the wreckage
revealed no evidence of any technical defects which could have contributed to the
accident.
It is noted that there were four defects recorded in the previous 30 days regarding heavy
aileron forces in the left wing down direction. This could have contributed to the aircraft
rolling to the right. However, these defects had been reportedly fixed at least three times
prior to the accident. When the flight controls were inspected after the aircraft was
recovered from the seabed and no issues were identified in the flight control system.
During interview the crew indicated as the aircraft approached touch down it looked and
felt as though the aircraft was going to touchdown on the left float, (upwind) for the
consideration of the current wind. Unexpectedly the aircraft bounced off the right float
with a very high pitch attitude. With this attitude the aircraft veered to the right, and they
did not recall any aural warnings.
According to the PIC; immediately the aircraft bounced after the first impact with the
water. PIC told the co-pilot he was taking control and called for a go-around, requesting
ten degrees flap, and added full power. PIC tried to lower the nose and get the wings level
with the objective to regain airspeed and directional control to fly the aircraft out of the
situation. PIC was unaware that the aircraft right wing tip dipped in the water as the
aircraft veered to the right after the unexpected bounce.
According to the co-pilot; when the aircraft impacted water, the PIC called for change of
control and the control was handed over. The co-pilot neither heard the PIC’s call for 10
degrees flap, nor took any actions to change the flap settings. During the investigation, it
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was confirmed that the flaps were at full down position. Proper procedures for the go
around were not followed which is indicative of CRM breakdown.
However, an enhanced video recording of the approach and landing of the aircraft
revealed that the aircraft touched water on the left float and bounced twice. The aircraft
then was seen making a steep turn to the right with a nose up attitude and the right wing
tip was seen contacting water. Next it was seen suddenly banking to the left and dropping
nose down into the water.
After the initial bounce, the aircraft would have been in a slow flight condition. The aircraft
yawed to the right, nose pitched up and the right wing tip dipped in the water. Combined
controls were used to counter the nose up attitude and initiate a go-around.
Studies of similar accidents involving same type of aircraft elsewhere in the world have
shown that if a go-around was initiated when the aircraft is in a high pitch attitude and
adding full power results in the aircraft lifting off the water in a very nose-high, right-wing-
low attitude. With full flaps selected and both wings in a stalled or semi stalled condition,
the aircraft would not accelerate or climb. This results in the wings stalling and a loss of
control.
The investigation revealed that similar conditions lead to the accident occurred on this
aircraft. The aircraft was in a pitch up condition when the PIC took over the controls and
added full power initiating go around while the flaps were still in full down position.
This resulted in the aircraft going into a stall condition with a pitch up and right wing low
attitude causing the right wing dig into water. The PIC’s action to counter the situation
resulted the aircraft rolling to the left with the left float digging into the water and
crashing.
The Aircraft Flight manual (AFM) states, “WARNING - With Flaps fully extended at 37.5,
any pitch attitude in the go-around manoeuvre greater than 0 degrees (level flight
attitude) may cause a rapid decrease in airspeed and possible stall". 2
2 Supporting information can be found in the DHC 6-300 AFM (page 4 -46)
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There were no aerodynamics issues identified in the accident.
There was no evidence of adverse medical conditions that affected the flight crew. Drug
tests indicated that neither the PIC nor the FO were under the influence of, or impaired
by, drugs or alcohol at the time of accident.
Weather was not a contributing factor in this accident.
The operator is approved to conduct DHC-6 type conversion and recurrent training
courses by the MCAA through Operations Manual Part D. The flight crew had completed
the required training as per the Operator’s OM.
2.6.1 Evacuation
All passengers and crew were evacuated safely without injuries. Some passengers
escaped through starboard emergency exit, while the rest escaped through the rear
starboard door although the latter is not a designated exit. The flight crew escaped
through the right cockpit exit.
No passengers or crew reported any difficulties in evacuation.
2.6.2 Emergency Response
As soon as all the passengers were evacuated, the flight crew and passengers were
rescued by a small boat used by a dredger located close to the accident site and later
transferred to an Airport rescue boat.
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3. Conclusions
a. The airplane was certified, equipped, and maintained in accordance with MCARs and
approved procedures.
b. There was no known pre-existing damage to the airplane, its systems, or
Powerplants.
c. The flight crew were properly certified and qualified for their duties.
d. Weather was not a factor in the accident.
e. During landing, subsequent to the second bounce, a go-around was attempted.
f. Full power was applied with the intention of performing a go-around while the
aircraft was:
. At low speed
. At a nose high attitude
. With flaps fully extended.
g. When the go-around was attempted, the right wing had stalled and dipped in water.
h. No appropriate briefings as stated in OM, part-B were conducted although the two crew flew together for the first time. This led to CRM (communication) breakdown.
The investigation identified the following causes;
a. Improper recovery techniques from a bounced landing; application of go-around
procedures whilst the aircraft was at low speed with flaps fully extended.
b. Breakdown of crew coordination during the attempted go-around.
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Accident Investigation Accident Report: 2017/01 Coordinating Committee 8Q-TMV accident at Velana International Airport
4. Safety Recommendations
Subsequent to the findings of the investigation of this accident, the AICC makes the
following recommendations to the MCAA:
Determine whether the airline procedures;
a. Allowing the aeroplane to operate with full flaps are consistent with a safely initiated
and implemented go-around manoeuvre in a DHC-6-300 aircraft from a stall or near-
stall condition.
b. Contain a bounced landing and recovery procedure on DHC-6-300 aircraft operated
on floats.
c. Include specific procedures and trainings covering the aircraft upset recovery in all
phases of flight.
Subsequent to the findings of the investigation of this accident, the AICC makes the
following recommendations to the Operator:
a. If not already implemented, to add specific procedures covering the aircraft upset
recovery in all phases of flight.
b. Coordinate with Type Certificate Holder to establish specific procedures pertaining to
bounced landing recovery on DHC-6-300 aircraft operated on floats.
c. To revise the crew pairing procedures to make the crew and dispatchers aware about
the experience of other crew members.
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Accident Investigation Accident Report: 2017/01 Coordinating Committee 8Q-TMV accident at Velana International Airport
Subsequent to the findings of the investigation of this accident, the AICC makes the
following recommendations to the Type Certificate holder:
a. To establish procedures pertinent to bounced landing and recovery on DHC-6-300
aircraft operated on floats.
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Accident Investigation Accident Report: 2017/01 Coordinating Committee 8Q-TMV accident at Velana International Airport
5. Appendices
a. Operational Flight Plan
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Accident Investigation Accident Report: 2017/01 Coordinating Committee 8Q-TMV accident at Velana International Airport
b. Passenger List
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Accident Investigation Accident Report: 2017/01 Coordinating Committee 8Q-TMV accident at Velana International Airport
The below photos show the damages to the aircraft caused due to the accident. 1: Damage to outer skin of rear baggage compartment door. Large dents on the
entire surface.
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Accident Investigation Accident Report: 2017/01 Coordinating Committee 8Q-TMV accident at Velana International Airport
2: Large dent and puncture on step strut attachment point on fuselage aft of rear baggage compartment door.
3: Step strut attachment point broken off leaving a hole. Cracks propagating from the damaged area
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Accident Investigation Accident Report: 2017/01 Coordinating Committee 8Q-TMV accident at Velana International Airport
5: 7” Puncture of fuselage skin above port side cabin window 6.
4: Sliding window on the port side deformed and pulled out of groove
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Accident Investigation Accident Report: 2017/01 Coordinating Committee 8Q-TMV accident at Velana International Airport
6: Step strut attachment point sheared off leaving hole of approximately 3” diameter on the fuselage skin below port side Pilot door
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Accident Investigation Accident Report: 2017/01 Coordinating Committee 8Q-TMV accident at Velana International Airport
7: Multiple cracks, fractures and major dents on the door. Door latch broken. Fuselage skin under door damaged and ripped off
8: Nose cone crushed inward due to impact when aircraft was being lowered to M5 dock
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Accident Investigation Accident Report: 2017/01 Coordinating Committee 8Q-TMV accident at Velana International Airport
10: Water damage to all flight deck avionic equipment and furnishings
9: Fuselage skin crumpled and deformed on top and side of fuselage where ropes went around it to hoist the fuselage out of water. Rivets sheared and mating flanges exposed
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Accident Investigation Accident Report: 2017/01 Coordinating Committee 8Q-TMV accident at Velana International Airport
11: Frame 239 cracked
12: Fuselage top skin and stringers bent and crumpled above ‘A Frame’
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Accident Investigation Accident Report: 2017/01 Coordinating Committee 8Q-TMV accident at Velana International Airport
13: Rudder was found to be cracked and split in half
13: Damage to R/H wing from STA 376.20 to 272.00 including damage to aileron
15: Damage from STA 376.20 to 322.00 L/H Wing
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Accident Investigation Accident Report: 2017/01 Coordinating Committee 8Q-TMV accident at Velana International Airport
16: Cracks on outboard longeron of R/H and L/H engine
14: Impact damage of L/H and R/H propellers. Both engines were submerged in water
18: Deformation of floats and spreader bars of both L/H and R/H floats. R/H float sheared
off on impact. L/H float obtained substantial damage on impact
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Accident Investigation Accident Report: 2017/01 Coordinating Committee 8Q-TMV accident at Velana International Airport
AICC : Accident Investigation Coordinating Committee ATC : Air Traffic Controller AOC : Air Operator Certificate COM : Communication CON : Conrad Maldives Rangali Island CVR : Cockpit Voice Recorder DHC-6-300 : Viking Air Twin Otter 300 Series EMMA : Equalised Maintenance for Maximum Availability ELT : Emergency Locator Transmitter FAA : Federal Aviation Administration FDR : Flight Data Recorder FO : First Officer ICAO : International Civil Aviation Organization lb : Pounds LH : Left hand LT : Local time MCAA : Maldives Civil Aviation Authority MCAR : Maldivian Civil Aviation Regulation METAR : Meteorological Aviation Report MLE : Male’ MNDF : Maldives National Defence Force NM : Nautical Mile NTSB : National Transportation Safety Board OM : Operations Manual PF : Pilot Flying PIC : Pilot in command PTT : Push-To-Talk POM : Pilot Operating Manual RCV : Reverse Current Relay RH : Right hand RWY : Runway TMA : Trans Maldivian Airways Pvt. Ltd. TRI : Type Rating Instructors UTC : Universal Coordinated Time VFR : Visual Flight Rules VRMM : Velana International Airport VMC : Visual Meteorological Conditions
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